Headline

Software Engineer @Tohands

About

I write the software that runs on hardware people use to make a living. For the past two years at Tohands, I've built the firmware and system software behind a smart POS calculator — now running on 10,000+ devices in Indian retail shops. C++17 on Yocto Linux, LVGL for the UI, kernel-level drivers for the thermal printer and barcode scanner, BLE, and a billing engine that stays responsive across 15,000+ SKUs. I also built the factory diagnostic suite: 9 automated tests that pushed first-pass yield to ~90%. Outside of work, I contribute to open source. An N-to-N graph routing feature I wrote was merged into Meta's OpenZL (reviewed by Yann Collet), and a CLI feature of mine ships in Serial Studio. I also run a YouTube channel teaching embedded systems — Arduino, ESP32 — along with in-person workshops. Most recently I've been working at the edge-AI end of things: voice pipelines on constrained hardware, microphone → STT → agent → device RPC, all on-device where it matters.

Location

Bangalore Urban

AI stack

antigravity

codex

Work experience

Software Engineer at Tohands, Jul 2024 - Present · 2 yrs 2 mos, Bengaluru, Karnataka, India, Built the firmware and system software for a smart POS calculator — the company's primary revenue line — from first prototype to 10,000+ devices deployed across Indian retail in 14 months. Built the merchant billing engine with sub-second SKU lookup across 15,000+ products on constrained hardware — SQLite query optimization, indexed search, input debouncing, and paginated result rendering to keep the UI responsive at a busy counter. Instrumented usage funnels and session completion with an offline-first Mixpanel sync. Owned thermal printer and barcode scanner support end-to-end: wrote the kernel-level drivers in Yocto Linux, the peripheral abstraction layer above them, and the LVGL UI on top. Coordinated with mechanical and operations teams to take both through production rollout. Built a 9-test automated factory diagnostic suite covering display, modem, audio, battery, Wi-Fi/BLE, and peripherals — after tracing a factory throughput bottleneck to manual testing. Raised first-pass yield to 90% and cut per-device test time by 60%. Designed a modular peripheral architecture that let new hardware variants reuse the same driver and UI layers, and shipped OTA firmware updates to the full fleet without bricking devices in the field. Stack: C++17 · LVGL · Yocto Linux · FreeRTOS · SQLite · BLE · CMake · Kernel drivers · REST APIs · Mixpanel

Software Engineer Intern at upliance.ai, Mar 2024 - Jun 2024 · 4 mos, Bengaluru, Karnataka, India, Worked on embedded software for a smart kitchen IoT device. • Built precise temperature control logic using ADC sensor data. • Designed a DFA-based state machine for safe, compliant device operation. • Optimized bare-metal ESP-IDF code for real-time performance on ESP32. Stack: ESP32 · ESP-IDF · C · ADC · State machines

Software Engineer Intern at JUU - A product Developed By Navapravartana Technologies LLP, May 2023 - Jul 2023 · 3 mos, Hyderabad, Telangana, India

Event Coordinator at Paradox, IIT Madras, Dec 2022 - Jan 2023 · 2 mos, Chennai, Tamil Nadu, India

SDE Intern at Techvanto Academy, May 2022 - Jul 2022 · 3 mos, New Delhi, Delhi, India

Education

Bachelor of Technology - BTech, Computer Science, Lovely Professional University

Bachelor of Science, Data Science and Applications, Indian Institute of Technology, Madras

Public links

github: https://github.com/avionicharshit-byte